Parton enthusiastically accepted the invitation to record. After all, the album Cover Stories – released Friday – benefits a good cause: War Child, an international nonprofit that aids refugee children. But in her own handwritten response, Parton told Carlile, “Honey, do me a favor. Don’t drop the key. I think I can handle it.”

Once Carlile heard the finished version, she realized she’d been one-upped. “Every gratuitous and show-offy note that I hit in that song,” Carlile reports, “Dolly hits it initially and then takes it higher. She just completely takes me to school.”

Parton was the first of several artists to sign on to the tribute project, which was inspired after Carlile and her wife, Catherine Shepherd, became the mothers to daughter, Evangeline, in 2014.

“One thing I just couldn’t reconcile was what I was reading in the news [about the refugee crisis] and the kind of lifestyle we were able to give our daughter,” she says. “It felt like a juxtaposition I just couldn’t ignore.”

Carlile came up with the remake concept because The Story is perhaps her most commercial and celebrated project; the title song itself has been featured in numerous commercials, TV soundtracks, and singing competitions. To find artists to perform the remaining tracks, Carlile turned to friends, as well as heroes. (Her only previous connection to Parton was a fan letter Carlile wrote a couple years back that Parton also responded to.)

Carlile snagged fellow Seattle band Pearl Jam to sing “Again Today” through her friendship with lead guitarist Mike McCready. “They let me sing harmony on it, which has been such a tremendous milestone in my career – to have gotten to sing with Pearl Jam,” Carlile says.

“Yeah, those two little sneaky guys,” Carlile says of Lambert’s and Stapleton’s surprise appearances. “That was pretty cool that they showed up. I felt like that was their way of kind of raising their hands and saying, ‘I believe in this, too.’”

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The British superstar had previously covered the song as an extra track on a special UK edition of 21, her sophomore album, but it was unreleased in the United States. Carlile was determined to move heaven and earth to include it on her album.

“Well, you know, she lives behind a fortress of mysticism,” Carlile says of Adele. “… It was just extremely difficult to get her approval. “

Besides months of letter-writing, phone calls, and reaching out to anyone with an Adele connection, Carlile also recorded a personal video plea, along with a cover of Adele’s “When We Were Young,” and posted it on YouTube in January.

“I even, at one point, just covered it myself because I was just so sure we weren’t going to get Adele involved,” Carlile says. “… But in the end, just in the very 11th hour, Jonathan Dickins, Adele’s manager, called me and said, ‘All right, we’ve gotten all the letters. We understand. Adele approves it. Well done. Good job on the project.’ It made my year.”

A couple of hours later, Carlile got a call from her manager with more good news: In its 10th year, The Story had finally been certified gold. Any other day that would have been the headline, but not this day.

“I was, like, that’s great,” Carlile says, “but we got Adele!”

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Carlile hopes to raise $1 million for War Child, and with pre-sales and contributions, she has already reached a quarter of that goal. Everyone involved donated their work to the cause.

Meanwhile, Carlile’s soon-to-be-3-year-old daughter, Evangeline, is oblivious to what she has inspired.

“She’s just beginning to understand,” Carlile says, “that Momma does concerts and shows.”